On stress wave interactions in liquid impact

There are many situations in which the impact of a liquid jet is of importance. Such an event induces stress fields that interact to apply localized compressive or tensile loading to the targets impacted. Initially, the surface sees compression, but, after a short time, tensile forces are also experienced. At later times, the flow of the rest of the following liquid onto the target applies a further loading of lesser magnitude. In this respect, jet impact differs from that induced by a drop having the same radius of curvature. Experimental and numerical studies of liquid jets hitting liquids are presented, with results showing the effects of a cavity collapse in a reactive material. It is shown that it is the jet impact that leads to ignition rather than other mechanisms in the observed behaviour. (C) 2004 Elsevier B.V. All rights reserved.